One cause of lower IQs might be traced to nutrition. WHO research suggests iodine deficiency accounts for losses of between 10–15 IQ points. However, according to Thailand’s 2012 Multiple Indicator Cluster Survey, only 71 percent of Thai households consume enough iodised salt, falling to 54 percent in the poorest households. There is again a huge regional disparity, with 82 percent of households in Bangkok and only 54 percent of households in Thailand's northeast consuming adequately iodised salt. The regions with the lowest IQs are those same areas with the highest iodine deficiency.